\documentclass{sig-alternate}
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\usepackage{epsfig}
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\usepackage{algorithm,algorithmic}
\input{preamble.tex}

\title {Efficiently Answering Reachability Query on Very Large Directed Graphs}

%\author{Ruoming Jin$^{\dag}$ ~~~ Helen Piontkivska$^{\delta}$ ~~~ Dong Wang$^{\dag}$\\ $^{\dag}$ Department of Computer Science \\ Kent  State University,  Kent OH 44242  \\ \{jin,dwang\}@cs.kent.edu  \\ $^{\delta}$Department of Biological  Sciences    \\ Kent State University, Kent OH  44242  \\ \{opiontki\}@kent.edu }

\begin{document}
\maketitle 

\input{Abstract.tex} 
\input{Intro.tex}
\input{PathTree.tex}
\input{OptPathTree.tex}
%\input{HubNode.tex}
\input{experiment.tex}
\input{Conc.tex}

%\begin{small} 
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\bibliography{paper,cikm,reachability}
\bibliographystyle{plain}
%\end{small} 

%\input{Apps.tex}

\end{document}
